严格反馈型随机非线性系统输出反馈滑模控制

研究了一类带有不确定性参数的严格反馈型随机非线性系统的输出反馈镇定问题,主要是采用变结构滑模控制方法(SMC)来设计镇定控制器。首先根据系统的结构和输出状态构造了随机非线性状态观测器,并针对结构参数的不确定性,采用梯度自适应调节律,然后基于系统的观测状态选择滑动模切换流形,给出了不含噪声激励的变结构控制律,并证明滑动模的可达性和闭环系统滑模运动的稳定性,最后讨论了滑模控制的抖振抑制问题。通过系统仿真,与其它鲁棒控制方法进行比较,证明了本方法不仅能够有效地镇定该类随机非线性系统,并且具有一些更好的控制性能。

Variable structure sliding mode control of a strict-feedback stochastic nonlinear system

The output-feedback-based stability problem for a class of strict-feedback stochastic nonlinear systems with parametric uncertainties is studied and a stabilization controller is designed mainly by adopting variable structure sliding mode controlling(SMC) techniques.Firstly a stochastic nonlinear state-observer is constructed according to the structural characteristics and the output states of the given system,and for the parametric uncertainties,an adaptive adjusting law is proposed via the states' grads.And then a sliding mode switching manifold is selected based on the estimated states from the state-observer,following which a SMC law is proposed.Both the accessibility of the sliding mode and the stability of the closed-loop system on the sliding mode surface are confirmed in the paper.Lastly it's discussed about how to eliminate transient flattering brought out by the SMC control law.By an illustrative system's simulation and comparison with another robust controlling method for such a system,it can be seen that the presented control scheme here is effective to stabilizing such a stochastic nonlinear system and has some better controlling performance.